Low
D.0 on Vaillant ecoTEC 65kW

This is not an error code, but rather a status message indicating the current heating power setting your boiler is using to warm your home.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Heatingpartialload,adjustablevaluesinkW

From this model's manual
Verified against the Vaillant Ecotec 65kw installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

D.1View →D.2View →

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